Protherm Bear 20 KLZ Quick start guide

Output range 17 – 44.5 kW
Continuous output modulation
Integrated 110 l hot water tank
Bear
EN
version
xxxx_01 - v.3 2/2007
Operation and
Installation Guide
20, 30, 40, 50 KLZ
Protherm spol. s r.o.
Pplk. Pľjušťa 45
909 01 Skalica, Slovakia
Tel.: [phone]
Fax: [phone]
www.protherm.eu
Your service organisation:
Stationary cast iron boiler

1
Bear 20 (30, 40, 50) KLZ
The boiler’s Serial no. is shown on the plate which is attached to the rear side of the control
panel. The control panel is accessible after removing the front cover.
In the section “Operating Instructions” you will find description of the boiler’s main functions
and guidelines on how to handle the boiler safely. The section “Installation Instructions”
is for skilled workers only.
Obsah
Table of contents
Introduction........................................... 2
OPERATING INSTRUCTIONS
Controls and signals............................. 4
Selecting Read mode ........................... 5
Selecting Setup mode .......................... 5
Schematic diagram of boiler control ..... 7
Error codes........................................... 8
Starting up and shutting down boiler.... 9
Boiler control......................................... 9
Protection functions............................. 10
Service and maintenance.................... 11
Warranty and warranty conditions ....... 12
Technical specifications....................... 13
Connection dimensions ....................... 15
Schematic diagram of boiler................ 16
INSTALLATION INSTRUCTIONS
Introduction.......................................... 17
Delivery completeness ........................ 20
Preparing for boiler installation............ 21
Installing the boiler............................... 23
Operating the boiler............................. 25
Service modes..................................... 27
Electrical connection of boiler.............. 28
Converting to different fuel .................. 29
Electrical wiring diagram..................... 31

2
1.The boiler and all the associated
equipment must be installed and used in
accordance with the installation design,
all the corresponding valid legal
prescriptions and technical norms and
with the manufacturer’s instructions.
2.The boiler may be installed only in an
environment for which it is designed.
3.After installation, the boiler may be put
into operation by an authorised service
organisation only.
4.The boiler complies with the prescriptions
valid in the Slovak Republic. When used
in the conditions of other countries, any
applicable deviations must be identified
and addressed.
5.In the event of a defect call the
manufacturer’s service organisation –
any unauthorised intervention may
damage the boiler (and possibly also
associated equipment!).
6.The service technician putting the boiler
into operation for the first time is obliged
to familiarise the user with the safety
elementsoftheboiler,theircharacteristics
and with the relevant required response
of the user, with the fundamental parts of
the boiler and manner of use of the
boiler. If this technician is also delivering
the boiler, he/she must ensure that the
original packaging of the boiler is
available for potential further transport
thereof until the moment of launch into
operation.
7.Check whether the delivery is complete.
8.Check whether the model and type
supplied corresponds to the type required
for use, i.e. check whether the data
relating the boiler settings stated on the
plate correspond with the data relating to
the local network supplying fuel (gas) to
the place of installation, or have this
performed by a professional technician
who shall install the boiler or put it into
operation.
9.Whenever you are not sufficiently certain
of how to control the boiler, seek out and
study all the corresponding instructions
in this Operation and Installation Guide
carefully and proceed accordingly.
10.Never remove or damage any markings
and signs on the boiler. Also store the
original packaging of the boiler in an
undamaged condition for potential
further transport in the case that the
boiler is not put into operation.
11. . . . When performing any repairs, only
original parts may be used.It is prohibited
to make any changes to the boiler’s
internal installation, or to interfere with
this in any way.
12. . . When shutting the boiler down for a
longer period of time, we recommend
that you close the gas supply and
disconnect the boiler from the electricity
network. This recommendation applies
in conjunction with the general conditions
stipulated in this Operation and
Installation Guide.
13.At the end of its useful life, the boiler or
its parts must be disposed of ecologically,
in a manner which avoids causing any
harm to the environment.
14. . The manufacturer is not liable for and
provides no warranty for damages
caused by the failure to abide by:
• the conditions stipulated in this Operation
and Installation Guide;
• prescriptions and norms;
• proper installation and operation
procedures;
• conditions stated in the Warranty
Certificate and the Service Book.
15. .If the boiler is delivered to the user by
the technician who also installs the
boiler, this technician is also obliged to
present to the user all the accompanying
documentation for the boiler (in particular
Introduction

3
the Operation guide, Service Book etc.).
If the boiler is not put into operation, the
original packaging of the boiler must be
available for the potential further
transport thereof.
Safety of equipment and people
• According to the findings of the SZÚ
Brno (National Testing Institute), the
boiler (as well as all its optional
accessories) complies with the
requirements of European Directive
90/396/EEC on gas-fuelled appliances
and European Directive 92/42/EEC on
efficiency, the European Directive
2006/95/EC on electrical means of
operation for use in certain voltage
ranges and the European Directive
89/336/EEC on electromagnetic
compatibility.
• The appliance is also approved according
to the European norms EN 677, EN 625,
EN 60335-01, EN 50165, EN 55014, EN
61000-3-2 and EN 61000-3-3.
• In order to operate and handle the boiler
in accordance with the purpose for which
it is designed in actual conditions of use
(hereafter referred to only as use), it is
necessary to abide also by additional
conditions – the most essential of which
(i.e. those which must not be omitted)
are found in the following regulatory
documents:
- in the design area: STN 06 0310 and
STN 06 0830;
- in the fire safety area: STN 92 0300;
- for installation and fitting (and repairs):
STN EN 1755 or STN 38 6460, as
applicable STN 38 6462, Decree no.
48/1982 Coll. (as amended by the later
prescriptions) and the binding
occupational health regulations;
- in time of running and operation: STN 38
6405.
- in the area of discharge of combustion
gases and air inflow STN EN 483,
company material – “catalogue of dual
piping for discharge of combustion gases
and inflow of combustion air designated
for type C gas appliances, i.e. in closed
“TURBO” version
• In addition to the above mentioned
documents, it is necessary when using
the boiler to proceed in accordance with
this Operation and Installation Guide
and the accompanying boiler
manufacturer’s documentation. During
use of the boiler any handling by children,
persons under the influence of
intoxicating substances, non-certified
persons, etc. must be prevented.
In practice situations may arise in which
the following essential measures must be
adopted:
• preventthe boiler from (even accidentally)
being switched on while conducting
inspections or working on the combustion
gases flue route or gas and water
distribution pipes by disconnecting the
boiler from electrical power supply also
by other means than only using the main
switch (e.g. by pulling the power cord
plug out of the power socket);
• shut the boiler down every time when
there are any (even temporary)
flammable or explosive fumes present in
the area from which combustion air is
supplied to the boiler (e.g. from paint
when painting, laying and spraying
molten substances, from gas leaks,
etc.);
• if it is necessary to drain water from the
boiler or from the whole system, the
water must not be dangerously hot;
• in the case of a water leak from the
boiler’s heat exchanger or when the
exchanger is clogged up with ice, do not
attempt to start up the boiler until normal
operating conditions have been
restored;
• when a gas leak has been detected or
the gas supply has failed, or in the case
of suspicion that this has occurred, shut
the boiler down, turn the gas supply off
and call the gas board or a service
organisation.
*e.g. TPG 800 01

4
Operating instructions
Operating instructions
Controls and signals
Main switch
The main switch (Fig. 1, Position 7) is
used to switch the boiler on or off. The
main switch is situated on the right side of
the boiler control panel.
Caution: The boiler must be put into
operation and switched on for the first time
by an authorised service organisation!
Control panel
On the boiler’s control panel you can
monitor current values and set the required
parameters.
Fig. 1
124
3
5
6
7
The control panel has the following control
elements (Fig.1):
1 Timer switch – sets attenuation of tank
heating and attenuation of heating water.
2 MODE button – transition into setting
mode.
3 Display panel.
4 button.
5 Pressure gauge – displays pressure of
heating water.
6 RESET button – to unblock errors.
7 Main switch – switches boiler on and
off.

5
Selecting Read mode
Selecting Setup mode
Setting hot water temperature
Press the MODE
button – the diode in
the upper left-hand
corner of the display
flashes and the diode
in the lower right-hand
corner is lit. Use the
button to set the required temperature
of hot water in the tank. The setting range
of hot water values is
--, 40, 44, 48, 52, 56,
60, 64, 68, 70˚C
. On setting the parameter
-- the boiler warms only the heating water
into the heating system. By pressing the
MODE button the selected value is saved
into the memory and the mode for setting
the heating water temperature appears on
the display.
Setting heating water temperature
In the heating water
setting mode, the
diode in the upper
left-hand corner of
the flashes and the
diode in the lower
right-hand corner is not lit. Use the
button to set the required temperature of
heating water into the system. The setting
range of heating water values is
--, 45, 50,
55, 60, 65, 70, 75, 80, 85˚C
. On setting
the parameter -- the boiler warms only the
hot water in the tank – the boiler works in
“summer mode”. By pressing the MODE
button the selected value is saved into the
memory.
Displaying heating water
temperature
After turning the
boiler on by pressing
the main switch, the
current temperature
of the hot water
will appear on the
display.
Displaying hot water temperature
After pressing
the button, the
temperature of the
heating water in the
tank will appear on
the display. In this
display the diode is lit in the upper left-
hand corner, which indicates the value of
the current hot water temperature in the
tank. If the parameter “--“ appears on the
display instead of a numerical value this
means that the boiler is not in priority hot
water heating mode but is only warming
the heating water into the system.
Note: Switch between the display of the
current temperature of the heating water
and the temperature of the hot water in
the tank using the button.
Other values on display
Without regard to displaying the
temperature of the hot water and
temperature on the heating water, one
of the following statuses is signalised by
means of the diode in the lower right-hand
corner:
• diode not lit – no requirement for
burning
• diode flashing – requirement for burning
from tank (requirement for additional
heating of hot water in tank)
• diode lit – requirement for burning from
room control unit
Displaying heating water pressure
Pressure of heating water in the boiler
is displayed constantly on the analogue
pressure gauge (fig 1, position 5).

6
Equithermal mode
Setting the equithermal mode, i.e.
selection of the equithermal curve slope
and parallel shift of the curve, is possible
only in the case that an outdoor sensor is
attached to the boiler.
Note: If no outdoor sensor is attached, the
boiler will not enable the user to transfer to
setting mode E and P.
Setting curve slope
Press the MODE
button until the
parameter E appears
on the display. At
the same time the
diode in the upper
left-hand corner flashes. Using the
button set the required curve E1 – E9
and subsequently confirm selection by
pressing the MODE button. In the case of
selecting the parameter E- the equithermal
mode is switched off. The required output
temperature of the heating water from the
boiler has a value according to the outside
temperature and the relevant set curve
(Fig. 2).
Parallel curve shift
Press the MODE
button until the
parameter P appears
on the display. At the
same time the diode
in the upper left-hand
corner flashes. Using the button set the
required curve P1 – P9 and subsequently
confirm selection by pressing the MODE
button.
Value shift of individual curves:
P1 - posun o -15 °C
P2 - posun o -9 °C
P3 - posun o -6 °C
P4 - posun o -3 °C
P5 - posun o +3 °C
P6 - posun o +6 °C
P7 - posun o +9 °C
P8 - posun o +15 °C
P9 - posun o +21 °C
P− - no shift
Fig. 2
Curve slope
Fig. 3
Parallel curve shift
The required temperature of the heating
water according to the curve set in advance
is reduced (P1 to P4) or increased (P5 to
P9) by the set value, or remains without
shift (P-).

7
Valid only for connection of outdoor sensor
Fig. 4
Schematic diagram of boiler control

8
Error codes
No flame – F1
Thissignalsautomatic
irreversibleblockingof
the automatic ignition
and closure of the
gas valve, i.e. LOSS
OF FLAME. This
blocking occurs always in the mode when
the gas valve is open and no feedback
signal about the presence of the flame is
sent. The boiler is switched off and cannot
be started.
This fault however may be caused by
intervention with the safety elements
– emergency thermostat and combustion
gas thermostat.
Press the RESET button (fig. 1, position 6)
to unblock the fault. If the fault persists call
an authorised service.
Sensor error – F2
This signals a fault
of the heating water
sensor or a drop in
temperature of the
heating water below
3°C. The boiler is
switched off and cannot be started. Call
an authorised service.
Boiler overheated – F3
This signals a heating
water temperature
higher than 95°C.The
boiler is shut down
and restarts itself
automatically after
the water has cooled.
Sensor error – F4
This signals a fault of
the hot water sensor.
Heating of the hot
water tank is blocked,
whilst the mode
of heating into the
system is not affected by this fault.
Outdoor sensor error – F5
This signals a fault
of the outdoor
temperature sensor
when equithermal
boiler regulation
is set. The boiler
continues unlimited in its activity, but the
heating water temperature is regulated
according to the value set on the boiler
(see “Setting heating water temperature”,
page 5).
If the boiler is not in equithermal regulation
mode this fault does not occur.
Timer switch
The timer switch serves for setting
attenuation of heating the hot water in
the tank, i.e. during the interval of the set
attenuation the boiler does not heat the
water in the hot water tank to maintain
temperature. The length of the attenuation
interval is set by the cogs on the perimeter
of the clock rotor. The interval is set to
where the cogs face outwards – see
diagram. There may be more than one
interval, i.e. there may be a number of
attenuations per day.

9
Starting up the boiler
Important: Putting the boiler into operation
and starting it up for the first time must be
performed by an authorised service only!
If you wish to start the boiler up after it has
been put into operation, make sure that:
1 the boiler is connected to the electrical
power supply;
2 all stop valves (heating water, hot water,
gas) underneath the boiler are opened;
3 the heating water pressure is lower than
indicated on the pressure gauge – red
adjustable hand (water in boiler must be
cold).
Turn the main switch (Fig. 1, position 7)
to the ON position (I). The boiler is ignited
and heats the hot water in the tank. After
this has been heated, the boiler heats the
water in the heating system – if the heating
water temperature is set and a command
for heating is sent from the regulator.
In the event of a safety boiler shutdown an
error code appears on the control panel
(see “Error codes”, page 8).
Unblock the boiler by pressing the RESET
button (fig 1, position 6). If the emergency
shutdown recurs after a short time again,
or if the boiler cannot be unblocked by
pressing the RESET button, call an
authorised service organisation.
Shutting the boiler down
The boiler can be shut down for shorter
periods by switching off the main switch.
If the boiler is to remain shut down for a
longer period of time, also remove the
flexible power cord plug from the socket
and close the gas inlet to the boiler. If
there is no danger of the boiler freezing,
water can be left in the boiler, in the
opposite case it is necessary to discharge
the water from the boiler and from the
system. If the arrangement of the heating
system enables this, upon disassembly of
the boiler discharge water only from the
boiler and leave water in the system so as
to avert danger of corrosion.
Starting up and shutting down boiler
Boiler control
Using the boiler without a room
control unit
When running in this mode, the boiler
maintains the selected heating water
temperature. No room control unit is
connected, the terminals for its connection
must be mutually interconnected (standard
factory setting).
Setting procedure:
• turn the main switch to the ON position;
• set the required heating water
temperature on the control panel.
Using the boiler with a room control
unit
The boiler maintains the selected
heating water temperature. Switching
of the terminals to the room control unit
connection is cancelled and the room
control unit is connected. The boiler is
switched on and off according to the
internal temperature of the room in which
the room control unit is installed. This
room must not have thermostatic valves
installed on heating radiators.
Important: On the control panel it is
necessary to set the heating water
temperature (temperature of the water
in the system), which will be capable of
covering thermal losses of the building
even at low outdoor temperatures.
Note: Use control units recommended and
supplied by the PROTHERM company,
which are designated and tested for the
given type of boiler. In the case of use of
other regulators we do not guarantee the
correct and full functioning of the boiler.

10
Operation of boiler with equithermal
control
The boiler regulates the heating water
temperature on the basis of outdoor
temperature changes. In the case of this
type of regulation it is necessary to set
the equithermal curve according to the
required heating water temperature. It
is also necessary to attach an outdoor
temperature sensor. The procedure for
setting equithermal curves is outlined on
page 6 of this manual.
Important: The room control unit and
outdoor temperature sensor must be
connected only by an authorised service.
Note: During all types of boiler regulation,
heating of the hot water in the tank always
has priority, i.e. when a command for
heating the hot water is sent from the
tank, the boiler automatically switches
to the mode of heating the hot water in
the tank. After heating the hot water to
the required temperature the boiler is
automatically switched to the regime of
heating the heating water into the system
and continues in the heating system.
Setting boiler output
The factory setting of the boiler is to
maximum output. In case of necessity it is
possible to adjust the output of the boiler
according to requirement (with regard to
the properties of the boiler). In the case of
heating the hot water in the tank up to the
required temperature the boiler always
works at full output.
Important: Change of setting of boiler
output must be performed only by an
authorised technician.
Protection functions
Continuous output modulation
This takes place on the basis of constant
comparison of the actually attained
values with the values requested (set) by
the user; this regulation is proportional,
i.e. in the case of a larger difference of
compared values the boiler works with a
higher output and vice versa.
Protection against freezing
When the temperature of the heating water
drops below 8°C, the boiler is automatically
started and heats the heating water.
Protection of hot water tank against
freezing
When the hot water in the tank drops
below 8°C, the boiler is automatically
started and heats the tank. This function
is active only in the case that heating of
the hot water in the tank is switched off.
Pump protection
There is a possibility of blockage of the
pump due to sedimentation of sludge in
its bearings when the pump is idle for a
longer period of time. Switch the pump on
for a short time when it has been in the
room continuously for 24 hours.
Running down of pump
After the boiler is switched off by the room
control unit the pump continues to ensure
circulation of water in the heating system
for approximately 1 minute (only in heating
mode).
Anti-cycling
After the boiler has been shut down in
heating mode it cannot be restarted
sooner than 1 minute after shutdown
and the temperature of the heating water
drops by 8°C.
Note: This does not apply when the boiler
has been switched off by the room control
unit.
Protection against overheating
The pump is switched on always when
the temperature of the heating water is
higher than was set by the user, or if the
temperature of the heating water is higher

11
than 85°C. The boiler is switched off when
the temperature of the heating water is
higher than 90°C (fault F3).
Running pump depending on
heating water temperature
The boiler enables setting running of the
pump after a certain selected temperature
has been reached.This function can be set
only by an authorised service technician.
Chimney draught control system
The boiler is equipped with a “Chimney
draught control system” (CDCS). Upon
an accumulation of combustion gases in
the boiler, i.e. in the case of insufficient
discharge of combustion gases, the CDCS
is activated and the boiler switched off
(inflow of gas into the boiler is shut off).
Power failure
Power failure will turn the boiler off. When
power supply is restored, the boiler will
automatically restart itself without losing
any of the operating parameters settings.
If an error code appears on the display
after electrical power supply restoration,
unblock the boiler using the RESET
button.
Note: The boiler may be blocked as a
consequence of overheating caused by
the pump being switched off as a result of
power failure. Rectify this fault by pressing
the RESET button on the boiler control
panel. If the fault persist call an authorised
service.
Safety valve
The boiler is equipped with a safety valve
with an opening pressure of 3 bar. DO NOT
TOUCH THE SAFETY VALVE! Whenever
the safety valve starts releasing heating
water, switch off the boiler, disconnect if
from the electrical power supply and call a
service organisation. If the heating system
repeatedly loses pressure, consult your
service organisation.
Important: All the mentioned electronic
protection functions are enabled only
when the boiler is connected to power
supply (the power cord plug is inserted
into a power socket and the main switch is
in the ON position (I).
Service and maintenance
Maintenance of boiler by user
According to requirement the boiler casing
is cleaned without removing the upper
cover. Cleaning is performed when the
boiler is disconnected from the electrical
power supply by switching off the mains
switch and removing the power cord plug
from the socket. If the surface of the boiler
is damp it can be switched back on only
after it has dried.
It is necessary to check the water pressure
in the heating systems once in a while and
if necessary top up the water. Water can
be added into the heating system after
the boiler has cooled to less than 40°C
(measured by the thermometer on the
boiler). Failure to abide by this condition
may result in leakage or cracks caused by
stress in the block of the boiler.
In the case of gas leakage it is necessary
to shut down the boiler, close the gas
valve and call a service organisation.
Protection against legionella
It is recommended to that the hot water
in the tank is either heated constantly
to a temperature of 65°C or that the
temperature of heating the hot water is
increased at regular intervals to 70°C
in order to eliminate the possibility of
the spread of Legionella pneumophila
bacteria or other types of bacteria.

12
Professional maintenance of boiler
Once per year, preferably before the
beginning of the heating season, we
recommend that the boiler is checked and
set by a service organisation. This check
is not covered by the boiler’s warranty.
The specific tasks to be performed are
specified in the Service Book.
This mostly concerns tasks such as
checking the function and state of the
burner, checking and setting output,
checking the tightness of connections
of the flue conduit, checking the boiler
exchanger, checking the hot water tank
and checking the state of the magnesium
electrode.
In this it is particularly important to verify
the functional capability of the safety valve
andalsoverifythe activity of theemergency
and combustion exhaust thermostat. This
check is performed upon every service
intervention on these elements.
We recommend that the state of the
magnesium electrode is checked within six
months of putting the boiler into operation.
Deterioration of the electrode depends
on the composition and hardness of the
water. Longer time intervals for checking
are stipulated by a professional service
according to the degree of deterioration
following the first check. If 60% of the
electrode has been used up and the time
interval is to remain same, the electrode
must be replaced with a new one. The
tank must not be operated with a depleted
electrode. The overall warranty of the
boiler does not cover defects caused
by corrosion in the case of a depleted
magnesium electrode.
Note: The depletion of the magnesium
electrode rod ensues from its protective
function, and for this reason replacement
thereof cannot be included within the
warranty.
Warranty and warranty conditions
The PROTHERM Bear 20 (30, 40, 50)
KLZ is covered by the warranty defined
in the Warranty Certificate, the Service
Book and by other conditions specified
in this Operation Guide and Installation
Guide (chapters Introduction and Boiler
installation).

13
Bear 20 KLZ Bear 30 KLZ
Category . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .II2H3P
Version . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B11BS
Ignition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .electronic
Fuel. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .G20 / G31 . . . . . . . . . . . .G20 / G31
Max. thermal input. . . . . . . . . . . . . . . . . [kW] . . . . . . . . 19 / 18 . . . . . . . . . . . . . . 28 / 27
Min. thermal input . . . . . . . . . . . . . . . . . [kW] . . . . . . . 13,5 / 12. . . . . . . . . . . . . . 20 / 19
Max. thermal output . . . . . . . . . . . . . . .[kW] . . . . . . . . 17 / 16 . . . . . . . . . . . . . 26 / 24,5
Min. thermal output . . . . . . . . . . . . . . . . [kW] . . . . . . . . 12 / 11 . . . . . . . . . . . . . . 18 / 17
Efficiency. . . . . . . . . . . . . . . . . . . . . . . . . [%] . . . . 90 - 92 / 89 - 91 . . . . . . . 90 - 92 / 89 - 91
Gas pressure
Supply pressure . . . . . . . . . . . . . . . . [mbar]. . . . . . . . .18 / 30 . . . . . . . . . . . . . . 18 / 30
Jet diameter . . . . . . . . . . . . . . . . . . . . [mm]. . . . . . . .2,65 / 1,7 . . . . . . . . . . . . 2,65 / 1,7
Gas consumption
(Q max.) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2,0 [m3/h] / 1,6 [kg/h] . . . 3,0 [m3/h] / 2,0 [kg/h]
Heating
Max. operating pressure . . . . . . . . . . . . [bar] . . . . . . . . . . . . . . . . . . . . .3
Min. operating pressure . . . . . . . . . . . .[bar] . . . . . . . . . . . . . . . . . . . . .1
Recommended operating pressure. . . . [bar] . . . . . . . . . . . . . . . . . . . 1 – 2
Temperature range . . . . . . . . . . . . . . . . [°C] . . . . . . . . . . . . . . . . . . 45 – 85
Water volume in boiler . . . . . . . . . . . . . . . [l] . . . . . . . . . .9,1 . . . . . . . . . . . . . . . . .11,6
Expansion vessel . . . . . . . . . . . . . . . . . . . [l] . . . . . . . . . . . . . . . . . . . . 10
Max. pressure in expansion vessel . . . .[bar] . . . . . . . . . . . . . . . . . . . . 3,5
Hot water
Max. supply pressure . . . . . . . . . . . . . .[bar] . . . . . . . . . . . . . . . . . . . . .6
Adjustable temperature range . . . . . . . [°C] . . . . . . . . . . . . . . . . . . 40 – 70
Hot water tank capacity . . . . . . . . . . . . . . [l] . . . . . . . . . . . . . . . . . . . .110
Hot water flow (Di according to STN EN 625)[l/min]. . . . . . . . 12,4 . . . . . . . . . . . . . . . . .14,0
Electrical data
Voltage . . . . . . . . . . . . . . . . . . . . . . . [V/Hz] . . . . . . . . . . . . . . . . . . 230/50
Input (max.). . . . . . . . . . . . . . . . . . . . . . .[W] . . . . . . . . . . . . . . . . . . . .130
Prot. cover. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . IP 40
Current . . . . . . . . . . . . . . . . . . . . . . . . . . [A] . . . . . . . . . . . . . . . . . . . . 0,5
Exhaust of combustion gases - method . . . . . . . . . . . . . . . . . . . into chimney
Flue diameter . . . . . . . . . . . . . . . . . . . [mm] . . . . . . . . . 130 . . . . . . . . . . . . . . . . 130
Combustion gas temperature . . . . . . . . [°C] . . . . . . . . . . 88. . . . . . . . . . . . . . . . . 116
Combustion flow mass . . . . . . . . . . . . . [g/s] . . . . . . . . . 13,3 . . . . . . . . . . . . . . . . 19,8
Min. required stable chimney thrust . . . [Pa] . . . . . . . . . . . . . . . . . . . . .2
Noise level (1 m from the boiler at height of 1.5 m)[dB] . . . . . . . . . . . . . . . . up to 55
Dimensions – height / width / depth . . [mm]. . . . . . . . . . . . . . . 1385 / 505 / 892
Weight without water. . . . . . . . . . . . . . . [kg] . . . . . . . . . 145. . . . . . . . . . . . . . . . . 160
Technical specifications 20 (30) KLZ

14
Bear 40 KLZ Bear 50 KLZ
Category . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .II2H3P
Version . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B11BS
Ignition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .electronic
Fuel. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .G20 / G31 . . . . . . . . . . . .G20 / G31
Max. thermal input. . . . . . . . . . . . . . . . . [kW] . . . . . . .38,5 / 36,5 . . . . . . . . . . . . 49 / 47,5
Min. thermal input . . . . . . . . . . . . . . . . . [kW] . . . . . . . 27 / 25,5. . . . . . . . . . . . . 36 / 32,8
Max. thermal output . . . . . . . . . . . . . . .[kW] . . . . . . . . 35 / 33 . . . . . . . . . . . . . 44 / 41,2
Min. thermal output . . . . . . . . . . . . . . . . [kW] . . . . . . . 24,5 / 23. . . . . . . . . . . . . 31,5 / 28
Efficiency. . . . . . . . . . . . . . . . . . . . . . . . . [%] . . . . 90 - 92 / 89 - 91 . . . . . . . 90 - 92 / 89 - 91
Gas pressure
Supply pressure . . . . . . . . . . . . . . . . [mbar]. . . . . . . . .18 / 30 . . . . . . . . . . . . . . 20 / 30
Jet diameter . . . . . . . . . . . . . . . . . . . . [mm]. . . . . . . .2,65 / 1,7 . . . . . . . . . . . . 2,65 / 1,7
Gas consumption
(Q max.) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4,1 [m3/h] / 3,3 [kg/h] . . . 5,2 [m3/h] / 3,8 [kg/h]
Heating
Max. operating pressure . . . . . . . . . . . . [bar] . . . . . . . . . . . . . . . . . . . . .3
Min. operating pressure . . . . . . . . . . . .[bar] . . . . . . . . . . . . . . . . . . . . .1
Recommended operating pressure. . . . [bar] . . . . . . . . . . . . . . . . . . . 1 – 2
Temperature range . . . . . . . . . . . . . . . . [°C] . . . . . . . . . . . . . . . . . . 45 – 85
Water volume in boiler . . . . . . . . . . . . . . . [l] . . . . . . . . . 14,1 . . . . . . . . . . . . . . . . . 16
Expansion vessel . . . . . . . . . . . . . . . . . . . [l] . . . . . . . . . . . . . . . . . . . . 10
Max. pressure in expansion vessel . . . .[bar] . . . . . . . . . . . . . . . . . . . . 3,5
Hot water
Max. supply pressure . . . . . . . . . . . . . .[bar] . . . . . . . . . . . . . . . . . . . . .6
Adjustable temperature range . . . . . . . [°C] . . . . . . . . . . . . . . . . . . 40 – 70
Hot water tank capacity . . . . . . . . . . . . . . [l] . . . . . . . . . . . . . . . . . . . .110
Hot water flow (Di according to STN EN 625)[l/min]. . . . . . . . 15,3 . . . . . . . . . . . . . . . . . 21
Electrical data
Voltage . . . . . . . . . . . . . . . . . . . . . . . [V/Hz] . . . . . . . . . . . . . . . . . . 230/50
Input (max.). . . . . . . . . . . . . . . . . . . . . . .[W] . . . . . . . . . . . . . . . . . . . .130
Prot. cover. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . IP 40
Current . . . . . . . . . . . . . . . . . . . . . . . . . . [A] . . . . . . . . . . . . . . . . . . . . 0,5
Exhaust of combustion gases - method . . . . . . . . . . . . . . . . . . . into chimney
Flue diameter . . . . . . . . . . . . . . . . . . . [mm] . . . . . . . . . 150 . . . . . . . . . . . . . . . . 180
Combustion gas temperature . . . . . . . . [°C] . . . . . . . . . 131 . . . . . . . . . . . . . . . . 115
Combustion flow mass . . . . . . . . . . . . . [g/s] . . . . . . . . . . 31 . . . . . . . . . . . . . . . . . .50
Min. required stable chimney thrust . . . [Pa] . . . . . . . . . . . . . . . . . . . . .2
Noise level (1 m from the boiler at height of 1.5 m)[dB] . . . . . . . . . . . . . . . . up to 55
Dimensions – height / width / depth . . [mm] . . . . 1385 / 505 / 892 . . . . . . . 1385 / 590 / 892
Weight without water. . . . . . . . . . . . . . . [kg] . . . . . . . . . 185. . . . . . . . . . . . . . . . . 210
Technical specifications 40 (50) KLZ

15
120
290
460
976
607
792
153
730
1385
50
a
c
892
869
e
Connection dimensions of boiler 20 (30, 40, 50)KLZ
TYPE
abc eød
20 KLZ 327,5 191 505 177,5 130
30 KLZ 285 106 505 220 130
40 KLZ 242,5 21 505 262,5 150
50 KLZ 285 21 590 305 180
Fig. 5
A – hot water input 3/4” B – hot water circulation 3/4”
C – hot water output 3/4” D – heating water input 1”
E – heating water output 1” F – gas input 3/4”

16
Fig. 6
1. Control panel 10. Backflow valve for HeW circuit 19. Hot water (cold water) inlet
2. “POLO-TURBO” superstructure 11. Backflow valve for HoW circuit 20. Filling and discharge
3. Combustion gas collector 12. Gas inlet 21. Burner plate
4. Automatic bleeding valve 13. Heating water outlet 22. Gas valve with ignition automatic
5. Safety valve 14. Boiler body 23. Hinged frontal cover
6. Pump for HoW heating circuit 15. Heating water inlet 24. Set for installation on HoW inlet
7. Combustion exhaust safety valve 16. Hot water tank 25. Expansion vessel for HoW circuit
8. Pump for HeW circuit 17. Hot water outlet
9. Expansion vessel for HeW circuit 18. Connection of HoW circulation
Schematic diagram of boiler

17
In the case of clogging of the system with
dirt from the heating system or incrusta-
tion sediments or problems caused by
other clogging (e.g. clogging of the heat
exchanger, pump defects) are not covered
by the boiler’s warranty.
Upon installation and operation of the
boiler it is prohibited in the sense of STN
92 0300 for objects (classified according
to STN 73 0823) to be placed at a distance
of less than:
- 100 mm in the case of materials which
are not easily flammable, flammable with
difficulty or medium flammable;
- 200 mm in the case of easily flammable
materials (e.g. chipboard, polyurethane,
polystyrene, polyethylene, sponge PVC,
synthetic fibres, cellulose materials,
asphalt strip, rubber and others).
Important: The surface temperature of the
upper parts of the boiler (particularly the
side walls and the cover) may exceed the
ambient temperature by up to 50°C.
A minimum manipulation (free) space
maintained around the immediate vicinity
of the boiler must be sufficient for a person
to work on it safely with bare hands and
with common hand tools (we recommend
a minimum distance of 300 mm on all sides
and min. 600 mm in front of the boiler).
The PROTHERM Bear 20 (30, 40, 50)
KLZ boiler is compatible with common
types of hot water heating systems and
heating radiators.
Important: The PROTHERM boilers must
be put into operation only by authorised
organisations according to Czech Bureau
of Occupational Safety and Czech Safety
Inspectorate Notice No. 21/1979 (in the
wording of Public Notice No. 554/1990
Coll.).
The boiler must be put into operation
and warranty and post-warranty service
must be performed by the manufacturer’s
contracted service organisation, which
meets the above specified requirements.
The boiler is designed to work in a normal
AA5/AB5 environment according to STN
33 2000-3 and STN 33 2000-5-51 (i.e.
within a temperature range of +5 to +40˚C
and humidity depending on temperature
up to maximum 85%).
The 20 (30, 40, 50) KLZ boiler must not be
installed in zones 0, 1 and 2, i.e. in rooms
with a bath tub, in bathrooms, washing
rooms and showers according to STN 33
2000-7-701 (Fig. 7).
The boilers are designed to run with
heating water compliant with STN 07 7401
(above all this water must not under any
circumstances be acidic, i.e. its pH factor
must be greater than 7 and must have a
minimal carbonate hardness).
The requirements for utility water
properties are defined in STN 83 0616 (for
drinking water STN 75 7111). If the water
has a combined calcium and magnesium
concentration greater than 1.8 mmol/l, it is
useful to implement other “non-chemical”
measures against incrustation (e.g. use of
magnetic water treatment combined with
a desludging device).
Installation instructions
Installation instructions
Introduction
Fig. 7
Zones

18
The boiler is designed for combustion
gases to be discharged (via a chimney
inlet) with a minimum stabilised thrust of 2
Pa.The boiler is connected to the chimney
inlet by a flue – for the boilers PROTHERM
20, 30 KLZ with Ø 130 mm, for the type
PROTHERM 40 KLZ with Ø 150 mm and
for the type PROTHERM 50 KLZ with Ø
180 mm.
Important: It is prohibited to place any
objects restricting the combustion gas
flow inside the flue (e.g. various types of
heat exchangers to utilise their residual
heat). The combustion gas exhaust flue is
not part of the boiler accessories.
Construction of the combustion gas
exhaust flue as well as that of the chimney
must comply with the requirements of STN
06 1610 and STN 73 4210. Compliance
with the principles specified by these
normswill prevent undesirablephenomena
from occurring, such as excessive cooling
of the combustion gases, penetration of
dampness into masonry and fluctuations
in the chimney thrust, and thus prevent
undesirable effects on the functioning of
the boiler.
The boiler takes combustion air from the
space in which it is installed.The minimum
size of such a space requires that there is
0.8 cu.m of free space per 1 kW of boiler
output, and in addition it must be possible
to ventilate the space directly. If direct
ventilation is not possible 2 cu.m of free
space is required for each 1 kW of boiler
output.
For discharge of combustion gases from
PROTHERM 20, 30, 40, 50 KLZ boilers it
is possible also to use the supplementary
device “superstructure PROTHERM PT 20
(30, 40) POLO – TURBO”, which ensures
the forced discharge of combustion gases.
It enables the operation of cast iron
boilers in cases where it is not possible
to use regular discharge of combustion
gases into a chimney. The superstructure
is designed for direct connection to the
combustion gas collector. The outlet of
combustion gases from the superstructure
is adapted for connection of single-
shell exhaust piping up to a length of 10
equivalent metres (1 equivalent metre = 1
metre of even section or 1 90° joint).
Mounting the superstructure onto the
boiler and putting into operation may
be performed only by an authorised
organisation according to Public Notice of
the Slovak Bureau of Occupational Safety
no. 74/1996 Coll. It is essential to abide
by the safety prescriptions during service
interventions into the superstructure when
this is connected to an electrical power
source (even when the mains switch is
off)!
The boiler is constructed for operation
with heating water up to an overpressure
of 400 kPa (4 bars), which compiles with
STN 07 7401 (this water must not under
any circumstances be acidic, i.e. its
pH factor must be > 7 and must have a
minimal carbonate hardness).
With regard to their properties, which
are unsuitable for operation of the boiler,
use of antifreeze compounds is not
recommended. This primarily concerns
reduction of heat transmission, large
scale expansion, ageing and damage to
rubber elements. If no other possibility
exists for reliably preventing freezing of
the heating system within the specific
conditions, failure to meet any of the
functional parameters or any defects of
the boiler as a consequence of use of
antifreeze compounds cannot be covered
by the boiler warranty.
The boiler may be used also in systems
with an open expansion vessel. In such a
case it is necessary to ensure an additional
check upon installation and if applicable
also adjustment of the factory setting of
the emergency thermostat temperature
– see point 3.4.
It is necessary to set the expansion vessel
with regard to the system – in the sense of
STN 06 0830 this ensures that the heating
system itself is secured up to a total
volume of 180 litres of water against quick
pressure fluctuations and undesirable

19
stress on all its elements during operation.
In cases where the total quantity of heating
water in the closed system exceeds 180 l it
is essential to include a second expansion
vessel in the system. This vessel must
have an identical same construction, i.e. it
must be closed, with a membrane.
The resultant value of the water pressure
in the system when cold is constantly
indicated by the red (adjustable) hand of
the boiler pressure gauge. If the pressure
drops beneath such an indicated value it is
necessary to seek and rectify any leakages
or to de-aerate the system more effectively
(or both). If pressure drops repeatedly and
the entire system is effectively sealed and
properly de-aerated, this most probably
represents a fault in the expansion vessel,
and it is essential to call an authorised
technician to rectify this fault.
Upon filling of the hot water tank it is
necessary to open the inflow and outflow
from the tank and allow the water to flow
out until it is entirely clear and without air
bubbles.
Before final assembly of the boiler it is
necessary to flush the distribution pipes
of the heating system several times with
pressurised water. In older, used systems
this must be performed against the flow
direction of the heating water.
Note: It is recommended to mount a
sludge trap in front of the boiler (i.e. on
the piping with return heating water). The
construction of this trap should enable
emptying at regular intervals without the
necessity of discharging a large volume
of heating water. The sludge trap may be
combined with a filter, a filter with a sieve
alone is not sufficient protection.
In the case of clogging of the boiler with dirt
from the heating system, these problems
or problems caused by other clogging are
not covered by the boiler’s warranty. The
filter and sludge trap must be checked
and cleaned regularly.
The requirements for utility water
properties are defined in STN 83 0616 (for
drinking water STN 75 7111). If the water
has a combined calcium and magnesium
concentration greater than 1.8 mmol/l, it is
useful to implement other “non-chemical”
measures against incrustation (e.g. use of
magnetic or electrostatic field).
The tank must not be exposed to the
effects of:
- higher pressures than the maximum
operational pressure;
- direct effects of fire or temperatures
higher than ordinary working and climatic
conditions
- impact, collision, force on the tank
vessel, shakes and vibrations (with the
exception of manifestations during actual
operation – i.e. circulation of heating
water and filling of utility water).
If the hot water issue points (cocks)
are located very far from the boiler, it
is possible to connect further piping,
creating a circuit with constantly flowing
hot water between the boiler and cocks
(hot water circulation circuit). A hot water
outlet is used for the piping from the boiler
to the cocks, the return piping from the
cocks to the boiler is connected to the
“circulation” outlet. With the introduction of
hot water circulation there is no discharge
of cold water from the cock. The hot water
supply is increased by the volume of the
circulation piping – the length of heating
may be perceptibly increased by this or at
the same time also by inefficient insulation
of the piping of the circulation circuit.
The pump for hot water circulation is not
controlled from the boiler and must meet
the hygiene requirements.
If there are special requirements for
relocation of the boiler (e.g. prevention of
damage to covers, limited passage profile
etc.) it is possible to partially disassemble
the boiler from the assembled state in
which it is delivered.
It is necessary to maintain a sufficient
space around the boiler in order to
ensure that handling of the boiler and
its accompanying equipment during
installation and operation can be
performed safely.